1. Field of the Invention
The present invention relates to an apparatus having a driven member and a drive controller therefor such as a camera having an image-blur correcting function.
2. Description of the Prior Art
To prevent unsuccessful photographing due to hand shakes, cameras having an image-blur correcting function have been developed. Today, many cameras come equipped with a zoom lens with an increasingly high magnification as their standard lens, and, as a result, photographing with long focal lengths is now considerably easy. However, this inevitably makes the effect of hand shakes felt more strongly than ever before, and therefore image-blur correction is a desirable function in cameras today; in fact, in movie video cameras, it is indispensable.
Conventionally, image-blur correction in a camera is achieved as follows. The light from an object is directed into an image-blur detecting optical system, where the light is passed through an imaging lens and is then received by an image-blur detecting sensor that is realized with a photoelectric conversion device such as CCD (charge-coupled device). When a hand shake occurs, this sensor detects the resulting image blur. Then, in accordance with the amount and direction of the detected image blur, an image-blur correcting lens unit driving system drives an image-blur correcting lens unit to be decentered in a direction perpendicular to the optical axis of the taking optical system in such a way that the image blur is canceled out. As a result, the image of the object is kept in the same position on the film throughout exposure.
However, to achieve image-blur correction as described above, a camera needs to be equipped with an image-blur detecting optical system and an image-blur detecting sensor, both of which require extra space inside the camera. This is inconvenient especially in compact cameras, because providing them with an image-blur correcting function results in making them larger and heavier, quite contrary to what is expected of such cameras.